Fetal Development/Transcript
Transcript Text reads: The Mysteries of Life with Tim and Moby An animation shows Tim and Moby throwing an egg back and forth to each other. TIM: Hey, too fast! Oh! Whoa! Oh! Moby almost drops the egg and throws it back to Tim. (Splat) TIM: Aaah. Well, I guess that was bound to happen. An animation shows Tim with the egg broken over his head and running down his face. An animation shows Tim’s handing holding a typed letter. Tim reads the letter with egg yolks. TIM: Dear Tim and Moby, how does a baby grow? From, Eric. The whole human development process starts when a female egg cell is fertilized by a male sperm cell. An animation shows several sperm cells moving towards a female egg cell. Once one of the sperm cells reaches the egg cell animation labels the egg cell and the sperm cell as "egg cell" and "sperm cell" respectively. At the top right, text reads: "fertilization". TIM: Women are born with about 100,000 egg cells, or ova, in their ovaries. An animation starts by showing a woman's silhouette and then zooms in to the lower part of her torso to show the internal reproductive organs. Both ovaries have lines drawn to them and are labeled with the text: ovaries. A cross section of the left ovary is magnified to show the egg cells. Text reads: "ova". TIM: When a woman hits puberty, her ovaries begin to release one egg into the fallopian tubes each month. An animation shows one of the ovaries and a fallopian tube. An egg, represented by a yellow dot, then starts moving from the ovary up the fallopian tube. A line is drawn from the fallopian tube to a label that reads: fallopian tube. A line is drawn from the ovary to a label that reads: ovary. TIM: While the egg is moving through the tubes, it can be fertilized by a male sperm cell. As the egg is moving down the fallopian tube, several sperm cells, represented by white dots, are moving in the other direction toward it. Once the sperm cells and the egg cell meet the animation zooms in on a cross section to show one of the sperm cells entering the egg cell. The magnified portion of the animation is labeled "fertilization". TIM: Out of the hundreds of millions of sperm cells released when a couple has sex, it only takes one to fertilize the egg. An image shows the female egg with one sperm cell entering it. Several other sperm cells surround the egg cell. Text reads: fertilization. TIM: The egg cell and sperm cell join together to make a whole new cell called a zygote, a fertilized egg cell. An animation shows an egg cell, represented by a light colored circle with a smaller round shape of a different color drawn in the center of the circle. A sperm cell is shown entering the outer portion of the egg cell and then moves towards the center of the egg cell. Once the sperm cell and the center portion of the egg cell become one, the egg cell increases in size. Text reads: zygote. TIM: The zygote divides into two cells, then four cells, then eight, and so on, splitting about once every 20 hours until it's a hollow ball called a blastocyst. A zygote is represented by a light colored circle with a thin white edge, with a smaller round shape of a different color drawn in the center. An animation then shows a line dividing the zygote in half, with a round shape of different color in each of the two halves. The halves are divided again to become four similar shapes, then splits into eight shapes of different sizes, and so on until a ball composed of egg cells is shown on the screen. Text reads: blastocyst. TIM: The blastocyst travels through the fallopian tubes and into the uterus, where it attaches to the lining about a week after fertilization. An animation shows one of the ovaries and a fallopian tube. A blastocyst, represented by a yellow dot, then starts moving through the fallopian tube. Once it reaches the end of the tube, the animation zooms in on a cross section to show the blastocyst attaching to the wall of the uterus. The ovary, the fallopian tube, and the uterus are all labeled. Text reads: blastocyst. MOBY: Beep. TIM: Yeah, the woman is pregnant now, and over about nine months that clump of cells will eventually grow into a baby. An image shows a blastocyst attached to the wall of the uterus. Text at the top left reads: pregnancy. Text at the bottom right reads: 9 months. TIM: Pregnancy is usually divided up into three trimesters, each consisting of about three months. A diagram shows the nine stages of fetal development. The stages are represented by nine boxes numbered one through nine. In each box there is a silhouette of a fetus, starting from a dot in the first box and ending with the silhouette of a curled-up baby in the final box. The label "first trimester" is above the first three boxes, the label "second trimester" is above the second three boxes, and the label "third trimester" is above the last three boxes. TIM: Things happen really fast in the first trimester! The first three stages of the diagram are highlighted. TIM: As the blastocyst divides, cells begin to specialize to form body systems, starting with the nervous system. After about two weeks, it becomes an embryo. An image shows a spherical, opaque membrane with a light colored, pea-shaped object, labeled "embryo", attached to its wall. Text in the top right reads: 2 weeks. Text in the bottom left reads: first trimester. Moby addresses the camera. The lights on his chest are lighting up. MOBY: Beep? TIM: Well, the embryo gets nutrients from the placenta, a tissue that connects it to the mother. An image shows a more developed embryo attached to the placenta via a tube. Both the placenta and the embryo are labeled. Text at the top right reads: 4 weeks. Text at the bottom left reads: first trimester. TIM: The placenta passes oxygen, water, and nutrients from the mother to the embryo through a tube called the umbilical cord. An animation adds a green arrow above the tube, pointing from the placenta to the embryo. The tube is labeled "umbilical cord". TIM: Waste from the embryo flows through the cord to the expectant mother, who gets rid of it. Another, purple arrow is then added below the umbilical cord, pointing from the embryo to the placenta. TIM: Your belly button is where your umbilical cord used to be attached. An image of an animated person's stomach is shown. MOBY: Beep. An animation shows Moby, and then the camera pans down to show him touching his midsection with one hand. TIM: Not you. During the first trimester, the embryo starts to develop limbs, a heart, and muscles. An image shows a more developed embryo attached to the placenta via the umbilical cord. Text at the bottom left reads: first trimester. TIM: Its eyes and ears move around to the right places on its head, and a doctor can even hear its heartbeat. An animation shows a woman lifting up her shirt to expose her stomach. A doctor had placed an instrument against the woman’s stomach and is watching an attached monitor. TIM: The mom-to-be can feel pretty tired during the first trimester, and can feel kind of sick as her body changes to accommodate the growing life. An animation shows the woman's face turn green. She turns her head away from the doctor and covers her mouth with her hand. TIM: At the end of the first trimester, the embryo has grown into a three-inch fetus. An image shows a fetus attached to the placenta via the umbilical cord. Text at the top right reads: 12 weeks. Text at the bottom right reads: fetus. Text at the bottom left reads: first trimester. MOBY: Beep? TIM: Actually, it's still got a long way to go. During the second trimester, the fetus continues to develop organs and body systems. An image shows the diagram of the nine stages of fetal development. The second set of three stages of the diagram is highlighted. Text at the top left reads: pregnancy. Text at the bottom right reads: 9 months. TIM: The brain grows a lot in the second trimester. An image of a silhouetted animated fetus is shown, with an image of a brain inside the head. The brain and the head grow quickly. TIM: Fetuses begin to sleep and wake about week 18 — some doctors even think they can dream! MOBY: Beep? TIM: Well, no one really knows what a fetus is thinking, but its brain waves look like those of a full-term baby at about 26 weeks. An animation shows a fetus wearing a cowboy hat and holding a lasso, riding a purple chicken with a horn through outer space. TIM: During the second trimester, an ultrasound can show if it's a boy or a girl. An animation shows a doctor performing ultrasound. An image on the ultrasound machine shows an image of a fetus in the mother's womb. TIM: Moms usually feel a little bit better during the second trimester — and by the fifth month, they can even feel the fetus moving around! An animation shows an expecting mother laying on a hospital bed and a doctor performing an ultrasound. A bump appears from inside her stomach. TIM: By the end of the 26th week, the fetus is about a foot long, and weighs a bit less than a kilogram. An image shows a more developed fetus in a womb attached to the placenta via the umbilical cord. Text at the bottom left reads: second trimester. MOBY: Beep? An animation shows Moby with the lights on his chest lighting up. TIM: Yep, the fetus has pretty much finished developing body structures by now, but it still has a lot of growing to do. An image shows a fetus in a womb attached to the placenta via the umbilical cord. TIM: In fact, it gets so big in the third trimester that it has to pull its knees up to its chest to make room in the womb. An image shows the diagram of the nine stages of fetal development. The last set of three stages of the diagram is highlighted. Text at the top left reads: pregnancy. Text at the bottom right reads: 9 months. TIM: Gravity starts to pull the big head of the fetus down so it turns upside down and moves lower into the abdomen, ready to be born. An animation shows a fetus rotating and moving lower within the silhouette of a pregnant woman until it is turned upside down. Text at the bottom left reads: third trimester. MOBY: Beep? TIM: It's true — most of us are born head-first. An animation shows Moby picking up Tim by his feet and holding him upside down above the ground. Tim, while hanging upside down, addresses the camera. TIM: Whoa! Um, what are you doing? MOBY: Beep. TIM: They don't really hold the newborns by their ankles. So you can put me down, I'm saying. TIM: Whoa, they don't really spank them either! Animation shows Moby holding Tim by his feet with one arm, and the other arm lifted and fingers splayed. (Slap) Category:BrainPOP Transcripts Category:BrainPOP Health Transcripts